EFFECT OF SULPHUR, GYPSUM AND COMPOST ADDITION AND TILLAGE METHODS ON SOIL PROPERTIES AND WHEAT PRODUCTIVITY IN SALINE SOIL

Abstract

Effective use of salt affected soils needs the development of the most efficient and suitable reclamation technology to optimize farm management and better crop yields. Different chemical methods and amendments are used to reclaim the salt affected soils, and after reclamation such soils may be used for sustainable agricultural production. Choice of a chemical amendment depends on its availability, cost, handling and time of application. A field experiment was conducted for two successive winter seasons 2014/2015 and 2015/2016 at Sahl El-Hossinia Agric. Res. Station, El-Sharkia Governorate, Egypt, to evaluate two tillage methods (surface and subsurface) and three soil amendments (elemental sulphur S, gypsum Gy, compost Co, compost + sulphur, compost + gypsum, gypsum + sulphur and compost + sulphur + gypsum) on some soil properties and wheat yield. The studied treatments were arranged within the experimental units in a split plot design in three replicates. Statistical analysis of grains and straw yield data showed that all the added amendments significantly increased the grains and straw yield of wheat compared with control. The addition of Gy+Co+S was the most effective addition in increasing the grains and straw yield in surface and subsurface tillage. Also, it is clear that grains and straw yields of wheat in the treatments of subsurface tillage were slightly higher than those in the treatments of surface tillage. Data showed that all applications of soil amendments under different tillage methods decreased soil pH and EC, but there is an increase in the values of organic matter and cation exchange capacity. This effect is more obvious in case of applying Gy+Co+S. Subsurface tillage associated by high values of O.M (%) and CEC (c.mole) than surface tillage. Soil OM (%) and CEC (c.mol/kg) were significantly increased as a result of added amendments. Data showed that values of total dry stable aggregates (DSA) and water stable aggregates (WSA) were increased in all treatments under study compared to control. The highest increase in values of total stable aggregates (DSA and WSA) was observed in the treatment of Gy+Co+S with subsurface tillage method compared to the treatments of surface tillage method and control. The highest values of hydraulic conductivity, total porosity, field capacity and available water were found by applying Gy+Co+S treatment in subsurface tillage method compared to control and other treatments of surface and subsurface tillage. The values of soil bulk density at different soil depths of all treatments were relatively low and the maximum decrease exists in case of the treatment Gy+Co+S with subsurface tillage method compared to other treatments and control. Generally, it can be concluded that gypsum, sulphur and compost application had decreased the hazardous effect of salinity of soil and hence exerted favorable effects on growth and yield of wheat. Subsurface tillage method improved soil chemical and physical properties which are reflected on growth and grain yield of wheat compared with the surface tillage method.